Humans don't have a lock on playing Santa, it seems; all creatures great and small, extinct or fantastic, can't get enough of Christmas. Falling in step with this duo's previous collaborations (What Dads Can't Do, etc.), their Santa has the requisite red suit and white beard, but he just happens to be a bright green dinosaur who can't shave ("No one would know him"), drive a car ("That would hurt the reindeer's feelings") or wear Bermuda shorts (he must adhere to his dress code)—and, in the upbeat finale, readers learn that he "can't wait for Christmas!" The breezy text has an underlying warmth, and Cushman's grinning dinos in human togs are good for a hearty ho ho ho. Ages 3-8. (Oct.)